#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <openssl/opensslconf.h>
#include <time.h>
#include "des_ver.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <openssl/des.h>
#include <openssl/rand.h>
#include <openssl/ui_compat.h>

'defines'
#define	EXIT(a) exit(a)
#define	BUFSIZE (8*1024)
#define	VERIFY 1
#define	KEYSIZ 8
#define	KEYSIZB 1024
#define	INUUBUFN (45*100)
#define	OUTUUBUF (65*100)
#define	ccc2l(c, l)
#define	l2ccc(l, c)
Funciones
void	usage (void)
void	doencryption (void)
int	uufwrite (unsigned char data, int size, unsigned int num, FILE fp)
void	uufwriteEnd (FILE *fp)
int	uufread (unsigned char out, int size, unsigned int num, FILE fp)
int	uuencode (unsigned char in, int num, unsigned char out)
int	uudecode (unsigned char in, int num, unsigned char out)
void	DES_3cbc_encrypt (DES_cblock input, DES_cblock output, long length, DES_key_schedule sk1, DES_key_schedule sk2, DES_cblock ivec1, DES_cblock ivec2, int enc)
int	main (int argc, char **argv)
Variables
char	key [KEYSIZB+1]
int	do_encrypt
int	longk = 0
FILE *	DES_IN
FILE *	DES_OUT
FILE *	CKSUM_OUT
char	uuname [200]
unsigned char	uubuf [50]
int	uubufnum = 0
unsigned char	b [OUTUUBUF]
unsigned char	bb [300]
DES_cblock	cksum = {0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00}
char	cksumname [200] = ""
int	vflag
int	cflag
int	eflag
int	dflag
int	kflag
int	bflag
int	fflag
int	sflag
int	uflag
int	flag3
int	hflag
int	error

Documentación de los 'defines'

#define BUFSIZE (8*1024)

#define ccc2l	(	c,
		l
	)

Valor:

(l =((DES_LONG)(*((c)++)))<<16, \
                         l|=((DES_LONG)(*((c)++)))<< 8, \
                         l|=((DES_LONG)(*((c)++))))

#define EXIT ( a ) exit(a)

#define INUUBUFN (45*100)

#define KEYSIZ 8

#define KEYSIZB 1024

#define l2ccc	(	l,
		c
	)

Valor:

(*((c)++)=(unsigned char)(((l)>>16)&0xff), \
                    *((c)++)=(unsigned char)(((l)>> 8)&0xff), \
                    *((c)++)=(unsigned char)(((l)    )&0xff))

#define OUTUUBUF (65*100)

#define VERIFY 1

Documentación de las funciones

void DES_3cbc_encrypt	(	DES_cblock *	input,
		DES_cblock *	output,
		long	length,
		DES_key_schedule	sk1,
		DES_key_schedule	sk2,
		DES_cblock *	ivec1,
		DES_cblock *	ivec2,
		int	enc
	)